213rf APPENDIX. 



Ceylon/ 1 by Mr. H. N. Moseley, now one of the naturalists in the " Challenger" expedition. The 

 author specially examined the genera Bipalium and Bhynchodemus ; and since my observations on 

 the former had been made some years ago, and printed off several months before the above 

 paper reached the Royal Society, a comparison of the results will be interesting. He agrees 

 with me in affirming that the skin closely conforms to the Planarian type. The flask-shaped 

 cells filled with " stabchenformigen Korpern" below the cutis he thinks homologous with 

 the "nail-like bodies of the Nemertines " but if he means by the latter expression the 

 proboscidian stylets, the homology is not very apparent, any more than the conjecture concerning 

 their possible alliance with the bristles of the Annelida. He makes the curious statement that 

 " it is commonly said that whilst in all other Vermes the external muscular layer is circular, and 

 the longitudinal internal, in Turbellarians the reverse is the case ;" but he might have observed, in 

 a paper on the " Anatomy of the Nemerteans/' 2 that considerable differences exist in the arrange- 

 ment of the muscular coats of the great groups — for example, between the Enopla and Anopla, the 

 external muscular layer in the former being circular, while in the latter it is longitudinal. With 

 regard to the nature of the pale areas described on p. 143, and which Mr. Moseley calls primi- 

 tive vascular trunks, I was in doubt after the examination of my specimen, though I could not 

 see anything nervous about them. If such be a water-vascular system it is totally different from 

 the circulatory trunks in the Nemerteans, which I hold to be the blood-vessels of the animals. 

 Some interesting theoretical remarks are appended to the communication. 



The latest publication pertaining to the subject is by M. E. Zeller, 3 on the " Structure of the 

 Proboscis of Borlasia Kefersteinii" Marion, the author having worked under the direction of the 

 latter. He is of opinion that the species must be united with that parasitic on the branchial 

 tissue of Bhalksia mamillata. It is therefore probably a similar — if not the same — form as 

 Delle Chiaje or Leuckart and Pagenstecher long ago described (see p. 2, &c). Unfortunately 

 the author is not more precise than M. Marion with regard to the anatomical position of the 

 proboscis, which, he states, is attached to the " walls of the general cavity." The complex struc- 

 ture of the anterior region is not precisely detailed, and the same remark is applicable, as in the 

 case of M. Marion, to his definition of the granular basal apparatus of the central stylet, which is 

 held to be brownish. He, however, has evidently more acquaintance than his colleague with the 

 muscular cavity (e in our figures) behind the floor of the anterior chamber, though his description 

 is somewhat obscure. Three marginal stylet-sacs are mentioned as characteristic of the species. 

 The dark layer above the styliferous apparatus would have been whitish by reflected light. He 

 agrees with M. Marion in calling the reservoir a poison-sac, but is not definite enough in his 

 account of the termination of its duct (which opens into the chamber s). The physiological 

 observations on the ejection of the proboscis have been anticipated. 



1 c Proceed. Roy. Soc./ vol. xxi, No. 142., received January, 1873 ; also in e Annals Nat. Hist./ 

 vol. xi, 4th ser., No. 64, April, 1873, &c. 



3 < Trans. Hoy. Soc. Edinb./ vol. xxv, p. 305, 1869. 



3 < Ann. Nat. Hist./ vol. ii, 4th series, No. 65, p. 398, May, 1873 (from the < Comptes Eendus/ 

 April 14th, 1873). 



ERRATUM. 



Delete the first synonym (date 1776) on p. 156, and the allusions thereto on pp. 10 and 158. 



